Time-switch mechanism



C. K. ERNST May 13, 1930.

TIME SWITCH MECHANISNL Filed Dec. 14, 1928 2 Sheets-Sheet l y 3, 1930. c. K. ERNST 1,758,222

TIME SWITCH MECHANISM Filed Dec. 14', 1928 2 Sheets-Sheet 2 2 V 33 J! Q 2 W Z n 5 /.5 v i l -ETmc MAIN LINE SNAP SWITCH /7 lf wse M T R THERMosrA-r /3 :1

SWI TC H 2f 1 FUEL FEEDER MOTOR 4 pang) 2".

15 02")? eyj Patented May 13, 1930 UNITED STATES CHARLES K. ERNST, OF BUFFALO, NEW YORK TIME-SWITCH MECHANISM Application. filed December I l, 1828. Serial No. 325,945.

This invention relates to an electric time switch mechanism which is more particularly intended. for startin the operation of a fuel feeding mechanism at a predeter ined time, and to alternately interrupt and resume such operation at predete mined intervals, although this time switch mechanism may also be used for other installations in which similar conditions exist.

It is the object of this invention to provide a time switch mechanism for this purpose which comparatively simple in construction and reliable in operation, and which can be readily set for beginning the cycle of op- 15 erations at any predetermined time, and to also become inactive and active at intervals which may be either regular or irregular as desired to suit the time of day or to meet other conditions.

In the accompanying drawings lligure 1 is a sectional view of a casing showing in elevation a preferred embodiment of my invention.

F ire 2 is a vertical cross section of the same taken on lii 22 Fig. 1.

Figure 3 is a fragmentary vertical section, on an enlai d scale, taken on line 33 2.

Figures 4: and 5 are fragmentary vertical sections, on an enlarged scale, taken on line 30 i 5 5 1, respectively.

Figure 6 is a horizontal section, on an en iargetl scale, taken on line 66 Fig. 1.

Figure 7 a fragmentary vertical section 7-7 Fig. 6.

is a perspective view of one of bio electric circuit closers of the time following description similar chareference indicate like parts in the drawings.

present case the electric time switch nechan 1 is shown in connection with an electric me or 10 which is adapted to operate mechanism of a furnace stokcr, and a m r 11 adapted to operate a blower or 1 whereby air it supplied to the furnace to promote combustion. This fuel u r Elle iu'el l'c feeding motor 10 is arranged in one branch circuit 12 and the blower motor 11 is arranged in another branch circuit 13, and these two circuits are arranged in parallel and adapted to be connected by a main manually operated switch 14 with the main lines 15 which supply the electric current.

In the branch circuit 13 containing the blower motor 11 is arranged an automatic thermostat switch 16 which in the present case is adapted to respond to variations in temperature of the boiler or furnace with which this air blower motor is connected, so .t when the temperature of the boiler or furnace drops below a predetermined normal degree the circuit of this motor will be closed so as to operate the blower and cause the fire to burn brighter.

When the ten'iperature again rises to the predetermined normal degree in the boiler or furnace, then the circuit of the blower motor will be broken and the operation of supplying air to the furnace or boiler will cease. The branch circuit 13 also contains a hand switch 60 whereby this circuit ,may be opened and closed manually at will.

The numeral 17 represents a snap switch which is arranged in one side of the main electric line between the main switch 14 and the two branch circuits containing the fuel feed motor and the air supply motor and which is adapted to open and close the main line quickly. This snap switch may be of any suitable construction but as shown in the drawings the same preferably consists of a rotatable stem 63 which upon being turned part of a complete revolution will quickly close the circuit and when turned another part of the same revolution, will quickly open said circuit, thereby turning the current from the main line on or off the branch circuit-s containing the blower motor and the fuel motor.

The numerals 18, 19, represent two stationary contacts of an electric switch which is arranged in a shunt circuit 20 around the fuel motor 10, these stationary contacts having bases 21, 22' whereby they are mounted and curved spring ends 23, 24 which are arranged side by side and are adapted to be bridged by a movable switch mechanism for closing the shunt circuit.

The opening and closing of the shunt circuit causes the branch circuit of the fuel motor to be opened and closed by means of two stationary switch contacts 26, 27 arranged in the fuel motor circuit 20, a movable bridge contact 28 movable into and out of engagement with the stationary contacts 26, 27, a rocking armature 29 connected with the bridge contact 28, a spring 30 engaging said armature and adapted to move the same in a dir ction for disengaging the bridge contact 28 with the stationary contacts 26', 27, and an electro-magnet 25 having its coil in said shunt circuit and adapted to attract said armature and move the brid e contact 28 against said sationary contacts 26, 27 and close the branch circuit of the fuel motor.

The time mechanism which controls the operation of the snap switch in the main line and the switch in the shunt circuit is preferably constructed as follows lVithin acasing 31 or other support is ar ranged a clock mechanism which may be of any suitable construction and which includes a minute shaft 32 adapted to make a complete rotation once during every hour. Upon this shaft is mounted a timing wheel or disk 33, preferably of fiber or other insulating material.

On this timing wheel are mounted in an annular row a plurality of the bridge contacts in such manner that during rotation of the timing wheel 33 the bridge contacts may be wiped against both of the contacts 23, 24 for closing the circuitof which they are a part, or the bridge contacts may be set on the timing wheel so that they will not bridge the contacts 26, 27 and therefore not close the circuit of which they form a part.

In the preferred construction each of the bridge contacts consists of a metal contact pin 34 projecting permanently rearwardly from the timing wheel and adapted to wipe over the curved free end 23 of the contact 18 during each rotation of the timing wheel, and a setable contact pin 35' mounted on the front side of the timing wheel but electrically connected with the companion rear contact pin 34 and adapted to either wipe over the curved end 24 of the contact 19 or to clear the same. For the purpose of thus permitting the setable contact 35 to be either operative or inoperative the same is arranged at one end of a pivot or wrist pin 36 which is journaled in a bearing 37 on the front side of the timing wheel and the opposite end of which is provided with a stop pin 38 arranged at right angles to the contact pin 35 relatively to the axis of rotation of the wrist pin 36.

When it is desired to make the setable pin 35 operative the same is turned away from the front face of the timing wheel and opposite to the direction of rotation of the latter so as to engage the stop pin 38 of the same with the front side of the timing wheel, as shown by full lines in Figs. 2, 5, 6 and 7 In this position of the setable contact pin 35 the same is practically rigid on the timing wheel and upon rotating with the latter will engage the curved contact end 24 and close the shunt circuit.

If it is desired to render the contact pin 35 inoperative the same is folded against the front side of the timing wheel in the direction of rotation of the same whereby the pin will clear the contact 24 upon passing the same and therefore not close the shunt circuit.

In the drawings, eight sets of contacts are mounted equidistant in a circumferential series on the timing wheel whereby it is possible to temporarily close the shunt circuit eight times during each hour upon setting the setable pins 35 all in an operative position. By turning every other setable pin 35 into its inoperative position on the timing wheel the shunt circuit is closed temporarily only four times during each hour, and by turning additional setable contact pins 35 into their inoperative positions the intervals between successive closings of the shunt circuit may be further lengthened to suit the particular conditions which are present.

The non-setable contact 24 which is engaged by the setable contact 35 is preferably fixed on a support 39 consisting of a plate of fiber or oth r insulating material mounted in the casing 31. The other relatively stationary contact 23 is capable of adjustment tangentially relatively to the non-setable contacts 34 on the timing wheel for the purpose of varying the duration of the engagement between the contacts 34 and the contact 18 and thus vary the amount of fuel which is delivered to the furnace by the operation of the fuel motor 10.

Various means may be employed for effecting the tangential adjustment of the contact 18, those shown in Figs. 1, 5, 6 and 7 consisting of a horizontally movable bar 40 carrying this contact and sliding in openings 41 formed in guide lugs 42 rising from a metal base 43 on the plate 39., and a screw nut 61 arranged on a threaded stem 44 on the bar 40 and provided with an annular groove 45 which receives a stationary pin 46 on the plate 39. Upon turning the screw nut 61 in one direction or the other the bar is moved tangentially relatively to the path of the setable contact pins 35 when the latter are in their operative position, and thereby cause these contacts to remain in engagement for longer or shorter periods of time, whereby the fuel motor 10 may be operated varying lengths of time and the amount of fuel delivered during each feeding operation may be regulated accordingly.

For the purpose of producing a friction tight mounting of the contact bar 40 with performed at y its guideway, the upper side of this bar is provided with tightening springs 47, which engage with sufiicient friction against the upper side of the guide openings 11 in the lugs $2 to maintain the parts reliably in their operative position and still permit of readily adjusting the same.

Assuming that the snap switch 17 and the main switch 1d are closed the operation of the apparatus thus far described is as follows As the timing wheel turns clockwise each of the setable bridge contact pins 35 which has been moved into its operative position will at the proper time engage with the contact 24 and as its companion bridge contact 34 engages the adjustable contact 18 at the same time the shunt circuit 20 is closed until the timing wheel has turned far enough to again disen age the bridge contacts 35 and 34 from the relatively fixed contacts 19 and 18.

The instant the shunt circuit is closed the electromagnet becomes energized and attracts the armature 29 whereby the bridge contact 28 coupled therewith is moved into engagement with the fixed contacts 26, 27 so as to close the branch circuit 12 containing the fuel motor 10 and causing t e latter to operate for supplying fuel to the .nace. V i the respective bridge contacts 3 3, 3% of the timing wheel clear the relatively fixed con tacts 24, 23 the shunt circuit 20 is broken, the electromagnet is tie-energized and the spring 30 moves the armature 29 and the bridge contact 28 in a direction for opening the branch circuit 12 containing the fuel motor so that the feedin o fuel is interrupted. The electro-magnet r the contacts associated with the same therefore serve as a relay switcl for quickly opening and closing the fuel motor circuit notwithstanding that the time wheel switch operates slowly, thereby pre venting arcing in this circuit and fusing of the contacts which otherwise would occur due to the heavy current required for operating the fuel motor.

By shifting a greater or small number of the setable contacts on the timing wheel into their operative position, the feeding of fuel by the motor 10 or similar function can be I rious predetermined periods as best sui the particular requirements.

Means are provided for automatically operating the snap switch 17 by motion derived from the clock mechanism for closing the :1 main electric circuit and causing the fuel feeding and air supplying blower, or other devices, to be rendered operative at a predetermined time.

In the preferred form, these means are con structed as follows:

The numeral 48 represents an operating arm which is secured to the rotary stem (33 of the snap switch and which is provided on its hub with a detent finger 19 adapted to en gage the freeedge of a detentspring catch on the snap switch housing and thereby prevent this stem and arm from moving backwardly upon reaching this position and also enabling the attendant to locate the operating arm 48 in the position which it should occupy when the contacts of the snap switch are disengaged but ready to be engaged for closing the main circuit in accordance with the setting of the trip mechanism which is operated at a predetermined time by the clock mechanism.

The numeral 51 represents a trip gear wheel provided with a trip pin 52 adapted to engage the operating arm of the snap switch and turn the same a suiiicient extent to close the contacts of this switch. Normally this trip wheel meshes with a driving gear wheel which forms part of the train of gearing the clock mechanism and which is rotated by the spring motor or other driving means of the clock in synchronism with the time mechanism in any well known and approved manner.

This trip wheel is mounted on a trip shaft .h can be moved lengthwise in its to permit of disengaging this trip a the driving wheel 53, as shown in F 4, then turning the trip n re-engaging the trip wheel with the driving wheel 53, as shown by full lines in Fig. 4.

The trip shaft and the trip wheel are releasrbly held in their operative position by means of a vertically swinging latch 5 pivoted. on the clock frame and movable into and out of engagement from an annular groove 55 in the trip shaft. The position of the trip shaft and wheel relatively to the clock mechanism may be indicated by a pointer 56 secured to the front end of the trip shaft and adapted to traverse a dial 57 on the adjacent partof the housing 31, which dial in the present case is calibrated so as to indicate twelve hours of the day.

If it is now desired to render the circuits operative at 6 oclock in the morning, so that the fuel feeder and blower motors would op erate to warm the building, or this apparatus were organized to perform some other func tion, and the setting of th mechanism secured at ten oclock on the previous day, then the trip wheel 51 would be uncoupled from the oi iving wheel 53 and turned so that the pointcr would be in line with the indication 8 on the dial and then the trip wheel is again coupled with the driving wheel.

It follows from this setting that the clock mechanism will turn the trip wheel idly for eight hours but at the end of the eight hours the trip pin engages the operating arm of the snap switch, as shown by full lines in Fig. 3, and as the trip wheel continues its rotation under the action of the clock mechanism the trip pin will shift the operating arm a sufficient extent, as shown by dotted lines in the same figure, to cause the snap switch to automatically complete its throw quickly independently of the trip wheel and thereby close the electric circuit in the main line for rendering the apparatus operative.

The snap switch may now be left in this closed position until some time after 6 oclock in the evening and then the attendant may again move the operating arm 48 into a position in which the snap switch opens the main circuit and this arm is in the path of the trip pin 52 ready to be shifted at 6 oclock a. m. the following day for starting the mechanism in operation.

This opening of the snap switch and setting the same for automatic closing must be effected each day if it is desired to bank the fire of the furnace in the evening, and then automatically cause the fire to burn more briskly in the morning.

If, however, it is not desired to bank the fire then the operating arm i8 need not be turned to close the snap switch in which case the current will be on all the time so long as the main hand switch 14: is closed.

If the setting of the pointer 56 occurs at i any other time of the day the position of the same relative to the dial 57 must be taken into consideration, for example, if the setting occurs at midnight then the pointer 56 would only be set back to the indication 6 on the dial inasmuch as the pointer would only have to travel from 6 to Zero on the dial, equivalent to six hours before the trip pin 52 would operate the snap switch and close the main circuit preparatory to resuming normal operation of the apparatus with which the timing mechanism is associated.

It will be apparent from the foregoing that by means of this timing mechanism the operation of various kinds of apparatus may 'be accurately controlled at predetermined periods and that the time of operation can be readily changed to suit different conditions and requirements.

I claim as my invention 1. A time switch mechanism for controlling an electric circuit comprising a clock mechanism, a timing wheel operatively connected with said clock mechanism, and means for intermittently opening and closing said circuit by motion derived from said timing wheel, including two relatively stationary contacts arranged on opposite sides of the timing wheel, a plurality of non-setable contacts mounted on one side of the timing wheel and adapted to engage successively with a sta tionary contact on one side of said wheel, and a plurality of setable contacts mounted on the opposite side of said wheel and adapted to engage with the other stationary contact.

2. A time switch mechanism for controlling an electric circuit comprising a clock mechanism, a timing wheel operatively connected with said clock mechanism, and means for intermittently opening and closing sald circuit by motion derived from said timing wheel, including two relatively stationary contacts arranged on opposite sides of the timing wheel, a plurality of non-setable contacts mounted on one side of the timing wheel and adapted to engage successively with a stationary contact on one side of said wheel, a plurality of setable contacts mounted on the opposite side of said wheel and adapted to engage with the other stationary contact, and means for adjusting one of said stationary contacts tangentially with reference to said timing wheel.

3. A time switch mechanism for controlling an electric circuit comprising a clock mechanism, a timing wheel operatively connected with said clock mechanism, and means for intermittently opening and closing said circuit by motion derived from said timing wheel, including two relatively stationary contacts arranged on opposite sides of the timing wheel, a plurality of non-setable contacts mounted on one side of the timing wheel and adapted to engage successively with a stationary contact on one side of said wheel, a plurality of setable contacts mounted on the opposite side of said wheel and adapted to engage with the other stationary contact, and means for adjusting one of said stationary contacts tangentially with reference to said timing wheel, comprising a sliding bar, a guideway for said bar, and means for shifting said bar lengthwise.

i. A time switch mechanism for controlling an electric circuit, comprising a clock mechanism, a timing wheel operatively connected with said clock mechanism, and means for intermittently opening and closing said circuit by motion derived from said timing wheel including two relatively stationary contactsarranged on opposite sides of the timing wheel, a plurality of non-setable contacts mounted on one side of the timing wheel and adapted to engage successively with a stationary contact on one side of said wheel, a plurality of setable contacts mounted on the opposite side of said wheel and adapted to engage with the other stationary contact, and means for adjusting one of said stationary contacts tangentially with reference to said timing wheel comprising a sliding bar, a guideway for said bar, and means for shifting said bar lengthwise, consisting of a screw threaded stem arranged on said bar, a screw nut working on said stem and provided with an annular groove, and a stationary pin engaging with said groove.

5. A time switch mechanism for controlling an electric circuit, comprising a clock mechanism, a timing wheel operatively connected with said clock mechanism, and means for intermittently opening and closing said circuit by motion derived from said timing wheel including two relatively stationary contacts arranged on opposite sides of the timing wheel, a plurality of non-setable contacts mounted on one side of the timing wheel and adapted to engage successively with a stationary contact on one side of said wheel, a plurality of setable contacts mounted on the opposite side of said wheel a d adapted to engage with the other stationary contact, and means for adjusting one of said stationary contacts tangentially 'ith reference to said timing wheel, comprising a sliding bar, a guideway for said bar, and means for shifting said bar lengthwise consisting of screw threaded stem arranged on said bar, a screw nut working on said stem and provided with an annular groove, a stationary pin engaging with said groove, and retaining spring means arranged on said bar and engaging said guideway.

6. A time switch mechanism for control ling an electric circuit, comprising a clock mechanism, having a driving gear wheel, a snap switch for opening and closing said circuit having a rotary stem and arm on said stem, a trip gear wheel provided with tip pin adapted to shift said arm for closing said switch, and a shaft carrying said strip wheel and movable longitudinally for engaging and disengaging said gear wheels.

7. A time switch mechanism for controlling an electric circuit, comprising a clock mechanism having a driving gear wheel, a snap switch for opening and closing said circuit having a rotary stem and an arm on said stem, a trip gear wheel provided with a trip pin adapted to shift said arm for closing said switch, a shaft carrying said trip wheel and movable longitudinally for engaging and dis engaging said gear wheels, and provided with a circumferential groove, and a retaining latch mounted on a relatively stationary support and movable into and out of engagement with said groove.

8. A time switch mechanism for controlling an electric circuit, comprising a clock mechanism having a driving gear wheel, a snap switch for opening and closing said circuit having a rotary stem and an arm on said stem, a trip gear wheel provided with a trip pin adapted to shift said arm for closing said switch, a shaft carrying said trip wheel and movable longitudinally for engaging and disengaging said gear wheels, a pointer arranged on said shaft, and a dial adapted to be traversed by said pointer.

9. A time switch mechanism for controlling an electric circuit, comprising a clock mechanism having a driving gear wheel,a snap switch for opening and closing said circuit having a rotary stem and an arm on said stem, a trip gear wheel provided with a trip pin adapted to shift said arm for closing said switch, ashaft carrying said trip wheel and movable longitudinally for engaging and disengaging said gear wheels, and provided with a circumferential groove, a retaining latch nonnted on a relatively stationary support and movable into and out of engagement with said groove, a pointer arranged on said shaft, and a dial adapted to be traversed by said pointer.

10. A time switch mechanism for control ling an electric circuit, comprising a clock mechanism, a snap switch for opening and closing said circuit having a rotary operating S-JGRI and an operating arm connected with said stem, a trip wheel operatively connected with said clock mechanism and having a trip pin adapted to shift said arm and close said snap switch, a detent catch mounted on a relatively stationary support, and a detent finger ,nged on said arm and adapted to be held at backward movement by said detent catch.

In testimony whereof I hereby afiiX my nature.

CHARLES K. ERNST. 

